How to Sharpen a Knife Using a Belt Sander

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When it is a matter of knife sharpening, there are various methods and devices to choose from. For many, a sharpening stone is simply the best medium to sharpen their knives.

If the collection of knives is large, the owner may have to choose other devices, as sharpening by hand can be significantly a time-consuming job. This is where a belt sander can be of great help.

Using it, you can sharpen knives safely as well as efficiently, provided you know how to use it and that you are not a beginner for the task of sharpening. Yes, a belt sander does require some practice to master. Still, it is the preferred device of many knife users as well as collectors.

A belt sander is a robust tool that is most useful for woodworkers. While rarely used for metal works, it does not mean that it is not useful for any other task. With the same power and efficiency, a belt sander is used for making as well as sharpening knives.

While a belt sander is not something that is used in daily life, it is likely to make you perform some tasks efficiently. For instance, you can use it to paint off something, smooth an item, and discard dust. So, investing in it will be valuable for you.

If you feel tough to cut vegetables or fruits with your knives or use a cleaver smoothly, knife sharpening belt sanders can easily solve this issue for you. This post guides you on why and how to use belt sanders.

Why Choose a Belt Sander for Knife Sharpening?

Sharpen a Knife Using a Belt Sander (Grizzly Industrial H6070 - 1" x 30)
Grizzly Industrial H6070 – 1″ x 30

The biggest reason why people have started sharpening knives using a belt sander is its speed. The tool is faster than the conventional devices meant for sharpening.

As a knife sharpening belt sander runs at a high speed, it easily delivers an immaculate edge in no time. This is unlike other sharpening tools or whetstones that consume time.

Another reason for using a belt sander is quite an easy sharpening. All you need to do is switch on the sander and pass the blade gently across it. The belt of the sander will then do the remaining work.

Obviously, nothing can overcome sharpening stones but sanders are among the easiest to use alternatives for skilled users. It is easier to use a belt sander than a sharpening stone, as it takes less effort when it comes to sharpening knives.

Another key benefit is that a belt sander generates a convex edge instead of a concave one, to the blade’s edge. This means you end up removing less metal and a lasting razor-sharp finish.

When it is a matter of sharpness, the sanders never disappoint anyone. Comparing a sharpening-stoned and a belt-sanded knife on the basis of sharpness will surprisingly show you no difference. You are assured to have the sharpest edge possible by using a belt sander.

Steps to Sharpen a Knife Using a Belt Sander

Before sharing the steps, it is essential for you to collect a few items for sharpening. Apart from a belt sander and the dull blade at the sharpening target, you need a 220 medium-grit belt, a honing compound, and a leather strop. You should always begin with a medium-grit belt.

Once you have these items, following are the steps to implement for sharpening a blade using a belt sander:

  1. Load the medium-grit belt into the sander. While loading, it is obvious that the belt should not be too tight. If it is, it will easily damage your blade. Similarly, you do not want it to be too loose. The belt should be loaded such that you can push it a bit back and yet have a bit of tension.
  2. Select the spinning direction for your sander. If you will be using the tool horizontally, ensure that it spins far from you. If it will be held vertically, the device must spin towards you. It is worth recalling that a lower grit means a rougher surface and consequently more abrasive impact on the blade. Keeping this in mind, pick the knife and stand in front of the device.
  3. Turn ON the belt sander to its maximum speed.
  4. Sharpen the blade. Take the blade and gently move it across the spinning device. While running across the sander, you should push the blade into it lightly. Avoid pushing too hard; just push it enough to have a bend on the belt. Applying a bit of tilt to the blade enables the device to hit the knife’s bevel. Stroke it for some time and then flip the side. Ensure that you hold the blade firmly using both hands and remain extra careful, as sanders shed off metal fast. Consider having one hand on the hilt and the other on the blade’s tip to enjoy maximum control over the strokes across the device. Do check for a burr after a couple of strokes. You will be astonished to see how quickly the sharp edge becomes visible.
  5. Allow your knife to cool. This can be done by keeping it in water. Okay, this step is something that you will find in a couple of guides. This is because it is not assumed as a step but as an inherent action. It is actually an important action or step to do. While sharpening using a belt sander, the probability of your knife being overheated is always high. If the blade is exposed to this heat level, it will get damaged. Thus, it is necessary to cool the blade, especially after every few strokes, to prepare it for another sharpening round. Although simple, this step prolongs the lifespan of your blade.
  6. Hone the blade. Once the sharpening is done, a good burr becomes visible on your blade. Honing your blade removes this burr. To hone, take out the medium-grit belt, insert the leather strop, and link it to your honing compound. Honing is done in the same way you sharpened your knife. Nevertheless, it is a vital step to get the sharpest blade. You will see that the burr is no longer visible after a couple of strokes.

Here is a good tutorial from Jon Peters – Longview Woodworking

Exploring the Right Grit

Rikon 50-161VS Power Tools 1 x 30 Inch Belt, 6 Inch Disc Variable Speed Sander
Rikon 50-161VS

Choosing the right grit for the sandpaper or belt is essential to get the desired level of sharpness. Usually, 100 grit is considered fine for the sharpening task. Many consider it to be more than enough.

However, if you have a knife made up of tougher material such as high-carbon steel or is a hunting knife that should be sharpened well, it is wise to choose 50 grit. A belt of 200 grit or more is ideal for having the sharpest possible edge with a smooth finish.

If you are just getting started with knife sharpening, it is wise to start with 50 grit and then gradually switch to 100 grit and more. However, if you are familiar with sharpening knives using a sander, a 50-grit belt can easily give you the desired sharpness level after which you can tune the edge using a 200 to 300-grit belt.

Thus, you will need the belt or sandpaper of different grits. Sharpening with a belt sander can be a complicated affair when the blade has deformed edges and grooves. For grooves, you need a very rough grit such as 25 and rub the edge down until all grooves disappear.

For this, you only need to hold the knife at 90 degrees on the sander and put a bit pressure to rub it down. When all grooves are gone, switch to the normal procedure featuring a belt of 50 to 100 grit for sharpening.

In case of bumped or twisted damages, stick to the normal sharpening procedure for a longer time than usual. Once over, switch OFF the sander and gently slash the knife perpendicularly onto the sander for removing the left-out dust.

The process of sharpening remains the same for all types of knives. However, only the technique and grits tend to differ.

Precautions to Be Taken While Using Belt Sanders for Knife Sharpening

Using a belt sander can be risky if you have never used it. This is because it can quickly grind off much blade metal and end up damaging the blade rather than sharpening it. You will see a jagged blade as the outcome. This decreases the lifespan of your blades.

So, if you choose to use a belt sander to enjoy its very quick and easy sharpening process with the right approach, it is important to take the following precautions:

  • Ensure that the surface on which you will be sharpening is free of dust.
  • Avoid keeping the blade for too long on the sander. Otherwise, it will face unwanted abrasion and result in a decreased lifespan.
  • Avoid raising the knife’s angle while sharpening so that it does not become blunter.


To sharpen a knife with belt sander means to get the sharpest possible edge faster than most other sharpening devices. It is also easy to use it but that needs some good amount of practice. There are also specialized belt knife sharpeners which work in a similar fashion.